The Health Behavior and Cancer Control Project is a survey study of health and illness behaviors that is being conducted in Los Angeles County. The survey features two main elements: 1. a study of urban health trends from 1974-1978, and 2. a one-year follow-up or longitudinal survey of adults from the trend study. Standard socio-medical indicators of acute and chronic illness, disability, use of health services and compliance with medical advice have been used extensively. In the follow-up survey data have also been collected on child health status, preventive health behavior, smoking behavior, health beliefs and social supports, knowledge and opinons related to cancer, breast self-examinations and mammography examinations. Some of the major research interests of the longitudinal survey include: 1. assessing individual health status, use of health services over time, 2. determining the role of health beliefs and social supports in influencing use of health services, compliance behavior and preventive health behavior, 3. analyzing opinions and knowledge regarding cancer, breast self-examinations and mammography. In addition, this study is investigating the use of the diary or memory aid technique and telephone interviewing in health survey research.